| Summary: | Glacial Movement Shows Trees Buried Long Ago. GLACIAL MOVEMENT SHOWS TREES BURIED LONG AGO JUNEAU, Alaska,—Great forests wiped out by glaciers only a few thousand years ago have been uncovered by a small recession of the Alaskan coastal glaciers, according to findings reported hy William S. Cooper, University of Minnesota glaciologist, in the Geographical Review. Shortly 'after the last great ice age, which ended only 20,000 years ago, the ice receded far up the valleys on the Alaskan coast, and great forests grew up on the well-watered valley floors. A period of cooling then caused a glacial readvance, and the forests were buried under frozen gravel and ice. Recently, the ice has melted, and the stumps of these ancient trees again are exposed. This recent retreat began only about 200 years ago, according to evidence supplied by rings in trees growing on the glacial deposits.
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